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By placing a satellite in an orbit with a radius of 22,000 miles the satellite goes around the earth once a day. If the orbit is about the equator the satellite appears to be stationary with respect to the earth. To minimize interference you must keep these satellites separate(no more than 90 in the orbit). Such satellites are used for broadcast TV and multiplexed phone conversations. Communication from earth to satellite uses microwave communications, which travels through clouds. Low-orbit satellites can also be used for communications systems: however, such a system is much more complicated because the antennas must follow a moving target and shift between satellites as they go over the horizon. Satellites make excellent communication relay stations because you do not need any ground network. Corporations establishing private communication systems outside the telephone system are big users of satellite communications. Third world countries such as India also make extensive use of satellite communications because it is much cheaper to reach the millions of villages by satellite than try to string copper or fiber cable. The emerging communication system will be a mixture of optical fibers between major nodes and of satellite communications in rural areas.